Cool/heat pump room air conditioner control circuits

Abstract

A control circuit for a cool/heat pump in which two separate motors are utilized, each with a main winding and an auxiliary winding. A single dual rated capacitor is provided in series with the auxiliary windings and an alternating current line and a selectively operative switch, which may be in the form of a thermostat, is provided in series between one of the alternating current lines and a main winding of one of the motors to selectively terminate power to that main winding while maintaining power to both auxiliary windings and the main winding of the other motor. Such a control circuit allows a de-icing operation with the cool/heat pump working in a heating mode, without blowing cold air into the room which is to be heated.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows: 
     
       1. A cool/heat pump operated by alternating current supplied on two lines comprising: a compressor driven by an electric motor with a main winding and an auxiliary winding;   an evaporator having a fluid flow connection to said compressor for a refrigerant fluid to flow from said compressor to said evaporator to absorb heat from the atmosphere surrounding said evaporator;   a condenser having a fluid flow path connection to said evaporator for said refrigerant fluid to flow from said evaporator to said condenser to release heat to the atmosphere surrounding said evaporator and a fluid flow path connection to return said refrigerant to said compressor;   a fan driven by an electric motor with a main winding and an auxiliary winding for causing a flow of atmospheric air over at least one of said evaporator and condenser;   a selector switch for a user to use in selecting an operating mode for the cool/heat pump, from the group comprising a heating mode and a cooling mode;   a temperature control thermostat operatively connected to a first of said alternating current lines to selectively energize said compressor motor in both said heating mode and said cooling mode;   a single dual rated capacitor connected between a second of said alternating current lines and both said fan motor auxiliary winding and said compressor motor auxiliary winding;   a solenoid for use in selectively changing the flow direction of said refrigerant fluid in said flow path so as to cause said evaporator and condenser to change their function to that of the other, said solenoid being operatively connected to said selector switch to provide for selective energization thereof;   a de-icer thermostat operatively connected between said fan motor main winding and said second line so as to terminate power to said fan motor main winding when said de-icing operation is in effect; whereby, said single capacitor can be used in conjunction with two separate motors, yet allowing only one of said motors to run during certain conditions, while maintaining full power to said other motor in said cool/heat pump.     
     
     
       2. A cool/heat pump according to claim 1, wherein said selector switch is in series between said second line and said fan motor auxiliary winding. 
     
     
       3. A cool/heat pump according to claim 1, wherein said solenoid is connected to operate a valve in said fluid flow connections to cause a change in direction of said fluid flow. 
     
     
       4. A cool/heat pump according to claim 1, wherein said selector switch has switch positions to provide an operating mode of energizing only the fan motor to the exclusion of the compressor motor. 
     
     
       5. A cool/heat pump according to claim 1, wherein said solenoid is connected in series between said de-icer thermostat and said second line such that when said thermostat terminates the power connection to said fan motor main winding it also terminates power to said solenoid. 
     
     
       6. A cool/heat pump according to claim 5, wherein said solenoid is normally energized when said selector switch is in said heating mode so that when said de-icer thermostat terminates power to said thermostat it also causes said fluid flow direction to change. 
     
     
       7. A control circuit for a cool/heat pump, said control circuit powered by alternating currents supplied on two lines and said cool/heat pump using a refrigerant fluid, wherein said cool/heat pump comprises means for compressing said fluid, said means having an inlet and an outlet, a first heat exchanger having a fluid flow connection to said outlet for said fluid to flow to said first heat exchanger, a second heat exchanger having a fluid flow path connection to said first heat exchanger for said refrigerant fluid to flow from said first heat exchanger to said second heat exchanger and a fluid flow path connection to return said refrigerant to said inlet, a fan for causing a flow of atmospheric air over at least one of said two heat exchangers, said control circuit comprising: an electric motor with a main winding and an auxiliary winding for driving said means for compressing said fluid;   a second electric motor with a main winding and an auxiliary winding for driving said fan;   a single dual rated capacitor connected between a second of said lines and both said fan motor auxiliary winding and said compressor motor auxiliary winding;   circuit means for selectively changing a flow direction of said refrigerant fluid in said flow path; and   circuit means for selectively terminating power to said fan motor main winding without also terminating power to said compressor motor.   
     
     
       8. A control circuit according to claim 7, wherein said first heat exchanger is a condenser. 
     
     
       9. A control circuit according to claim 7, wherein said second motor drives two fans to cause a flow of atmospheric air over both of said heat exchangers. 
     
     
       10. A control circuit according to claim 7, wherein said circuit means for selectively changing said fluid flow direction comprises a solenoid selectively controlled by said means for selectively terminating power to said fan motor. 
     
     
       11. A control circuit according to claim 7, wherein said circuit means for selectively terminating power to said fan motor comprises a thermostat. 
     
     
       12. A control circuit according to claim 7, wherein said thermostat senses the temperature associated with said first heat exchanger. 
     
     
       13. A control circuit according to claim 7, including a selector switch for a user to use in selecting an operating mode for the cool/heat pump, from the group comprising a heating mode and a cooling mode. 
     
     
       14. A control circuit according to claim 10, wherein said solenoid is connected to operate a valve in said fluid flow connection to cause a change in direction of said fluid flow. 
     
     
       15. A control circuit according to claim 10, wherein said solenoid is connected in series between said de-icer thermostat and said second line such that when said thermostat terminates the power connection to said fan motor main winding, it also terminates power to said solenoid. 
     
     
       16. A control circuit according to claim 15, wherein said solenoid is normally energized when said selector switch is in said heating mode so that when said de-icer thermostat terminates power to said thermostat it also causes said fluid flow direction to change. 
     
     
       17. An electric circuit comprising: two electric motors, each having a main winding and an auxiliary winding;   one dual capacitor having a central connection and two terminal connections;   a pair of alternating current lines; a first one of said lines being connected to said main and auxiliary windings and a second of said lines being connected to said central connection;   said two terminal connections being connected to said first line in series with the respective auxiliary windings of said two motors; and     selectively operative switch means in series between said second line and one of said main windings to terminate power to said one main winding, while maintaining power to both auxiliary windings and the other main winding.   
     
     
       18. A circuit according to claim 17, wherein said circuit is used in a cool/heat pump having a fan and a compressor and one of said motors which has said one of said main windings drives said fan while the other of said motor drives said compressor. 
     
     
       19. A circuit according to claim 18, wherein said cool/heat pump further comprises an evaporator and said switch means comprises a thermostat associated with said evaporator.